Open Excel
Click the cell where you want the calendar
Go to the Insert tab
Click Date and Time or Calendar, if available
Select the calendar control or template
Insert the calendar into the worksheet
Resize and position the calendar as needed
Save the workbook
If Calendar is not available
Go to File
Click New
Search for Calendar templates
Choose a calendar template
Click Create
Customize the dates and layout
Save the file
If you want a drop-down date picker
Enable the Developer tab
Click Insert
Choose More Controls
Select Microsoft Date and Time Picker Control, if available
Draw the control on the sheet
Link it to a cell
If you want a formula-based calendar
Create a month header
Enter the first date of the month
Fill the remaining dates using formulas
Format the cells as dates
Add borders and alignment